Archive for May, 2015

Lubrication FAQ

Friday, May 29th, 2015

Lubrication helps reduce bearing friction, transfer heat, and protect bearings from corrosion. This allows bearings to have a maximized life span, and perform optimally day-to-day. For such a simple idea, there sure is a lot to know about proper lubrication techniques. Manufacturers continue to create specialized lubricants and lubricators for various different applications. Follow the tracks through this lubrication FAQ for guidance.

What’s elements make a good all-purpose industrial grease?

You’ll want to look for a lubricant that protects against rust, corrosion, and general wear. For industrial bearings which operate at higher temperatures, look for assurance that the product is made for operating temperatures up to 300° F and “extreme pressure”.

An all-purpose lubricant with these characteristics will be well-suited for most industrial applications, such as: wheel bearings, axles, ball joints, U-joints, power takeoffs, off-road applications, and bushings.

What about synthetic lubrication for industrial applications?

Take a look at our previous post about synthetic lubricants here. In some instances, synthetic greases are superior to petroleum-based oils in their ability to resist breakdown from mechanical and thermal conditions.

Synthetic lubricants can provide the same bearing protection as natural greases. They can be formulated to endure high-pressure applications, inhibit corrosion, and prevent wear and oxidation. Designed for a variety of industrial, agriculture, and construction applications, synthetic lubricant can be especially well-suited for press-section bearings and calendar bearings.

Before using synthetic oil grease for your application, contact your sales or service engineer to be sure it is acceptable.

Is there lubrication specific to the food industry?

Food-safe lubrication is manufactured for food processing environments where there is a possibility of incidental food contact. You’ll want to be sure the lubrication you choose was formulated in compliance with CFR Title 21 Section 178.3570 and meets the requirements set by NSF H1.

Look for characteristics such as “food-safe”, “anti-wear” and “inhibits corrosion and oxidation” for long-life and optimal performance. This type of lubrication is best for food and beverage industry applications, as well as pharmaceutical industry applications.

When should I choose a lubricant with EP, or extreme pressure additives?

If your application will cause high axial or thrust loads, EP additives will be beneficial for you. If used in situations where there is not a high axial or thrust load, fatigue life of the bearing life may be reduced.

How do I clean out the lubricant from my bearing?

Wipe off all the lubrication you can reasonably reach. Then, wipe all surfaces with hydrocarbon solvent. This could be mineral spirits or kerosene. End with an isopropyl alcohol wipe. This process will work for both mineral and synthetic oils and greases.

If there is oil separation in my grease can I still use it?

Yes. Grease lubricants are formulated to release oil to be effective. Lighter grade grease will be more prone to oil bleeding. When compared with the amount of grease in the container, the amount of oil separation is normally insignificant, and can be safely stirred back into the rest of the grease prior to use. To prevent oil separation, keep storage temperatures consistent.

Why has the color of my lubricant darkened? Is it still OK to use?

Yes, it’s OK to use. Additives sometimes darken when exposed to sunlight, UV light, air and temperature changes. This is a result of the oxidation of those additives, but since they typically make up a small portion of the overall formula, there would not likely be any functional change.

Electric Motor Quality (EMQ) and the ABEC System

Friday, May 22nd, 2015

If you’ve been in the bearing industry a while you’ve likely come across the terms “electric motor quality” or “EMQ”, and perhaps also the “ABEC System” used for quality ratings.

Whether you’re new or experienced to the world of machinery, we’ll take you through a brief overview of what this terminology means, and how exactly it is supposed to be helpful to you.

We already know the EMQ stands for Electric Motor Quality, and that sounds like a great thing. If you’re using a certain part, you probably want that part to have a high degree of “quality”, but where does that seal come from?

This is a term that is freely used when describing bearings that meet a perceived “higher” level of quality than those meeting the standard quality of ABEC-1 (we’ll decrypt that in a moment). And, furthermore, this is a term that the manufacturers add to their own products.

We put an awful lot of trust in those big manufacturers, so hopefully they are indeed steering us in the right direction. Don’t fret, it helps both the consumer and the company when their perceived higher quality EMQ bearings are used and reviewed as truthfully being high quality by the consumer again and again. So, it wouldn’t do NTN or Timken or NSK any good to sloppily label a bearing as EMQ if it is not up to par.

The ABEC system is another way bearings are rated. ABEC stands for Annular Bearing Engineers Committee, and is part of the American Bearing Manufacturers Association, whose standards have been accepted by the American National Standards Institute and go along with the standards set by the International Standards Organization, better known as ISO.

This chain of checks and balances should help assure you that when purchasing, seeing bearings that have been rated under the ABEC system, you’re going to get a better quality bearing.

Bearings rated with this system are typically referred to as “precision bearings” and are rated using a scale from 1 to 9. The higher numbers are associated with higher precision standards. Thus, the higher the number, the higher tolerances that bearing can handle, and likely the higher the cost.

In the higher rated ABEC bearings, there is higher dimensional accuracy, and running accuracy. This means they will run smoother at higher speeds, even when the capacity and clearance are the same as “normal” bearings.

It is important to note that the ABEC and ISO bearing standards are primarily concerned with bearing tolerances, and while this is an important factor for the performance of a bearing, there are also many others that will affect bearing performance within different applications.

ABEC and ISO standards do not cover: radial play, raceway curvature, surface finish, material, ball complement, number, size or precision level, retainer type, lubrication, torque, cleanliness at assembly, packaging and other factors that may be essential to the desired bearing performance. 

Hopefully this overview of bearing rating systems will help you as you continue to rate the bearings you currently work with, and influence future design or purchasing choices.

Timken Integrated Flexpin Bearing Review

Friday, May 15th, 2015

Timken’s innovative take on this flexpin bearing merits review and praise. In this post, we’ll take a look at how the integrated flexpin bearing works, as well as its field test results. Then, you can decide if this flexpin bearing will improve application performance in your field.

Let’s begin with the unique features of Timken’s integrated flexpin bearing:

Thanks to high engineering, compared with a traditional planetary gear system, this integrated flexpin, or flex drive, is capable of providing greater power. This is because of its increased torque capacity within the same allotted space.

The design of this flexpin bearing features pins pressed into just one wall of the gear set carrier. An annular sleeve and bearing assembly then support the gear at the free end of the pin. The opposing forces in the pin and sleeve offset each other when under load, which results in no misalignment even across a wide range of torque.

This simple gear design sets the stage for a greater amount of torque reduction. This integrated flexpin bearing is built on the double cantilever beam principle. Its flexibility creates a system for the planet gears to carry a more unified load. The system is also set with preloaded tapered roller bearings, which provide for more equal load carrying capacity as well.

Machine designers are enabled to create new and substantially beneficial systems downsized from the conventional, or upgraded in terms of horsepower within their existing machines.

Overall higher levels of performance will be realized with the introduction of this system, particularly for those very challenging applications, such as – aerospace gearboxes, construction equipment final drives, and wind turbine gearboxes.

Complete list of applications, as noted by Timken – Gear drives in aerospace, agricultural, defense, heavy industry, and mining applications.

Next, let’s take a look at how Timken’s integrated flexpin bearing stood up to their rigorous testing:

The first test is validation testing, which revealed that K gamma is reduced to 1.07 at 100% load, using seven planets.

The second test is static bench testing, which was performed at the Timken Technology Center, and validated the Timken deflection model as fully functional.

The third test was done at Maag Laboratories, and confirmed load patters up to 200% of rated capacity.

It looks as though the Timken flexpin bearing has stood up to the design standards, and testing requirements set forth by Timken. More and more design improvements are being revealed on the market to satisfy the need for faster, more compact, and more accurate manufacturing.

This review highlights just one of those design improvements. Of course, it’s always up to you, the consumer, as to whether or not you’ll take a shot at trying out these innovative new designs. That’s why we at least want you to have all the facts.

Q&A: What Are Linear Motion Bearings?

Friday, May 8th, 2015

In this post, we’ve put together a brief answer to the question – what exactly is a linear motion bearing?

Linear motion bearings are designed to provide free motion in one direction by hand, inertia, or use of a motor. They utilize the combined efforts of linear drive systems (ball and roller screws) and linear guides and tables.

Linear drive systems generally use screws to transfer a rotary into linear movements. The second part of Linear Motion are linear guides and tables. The key when pairing these is to find the most suitable guiding solution for your application, which provides the needed accuracy, stiffness, positioning, and is available or made at an appropriate cost.

The linear ball bearing, also referred to as ball bushing or shaft guiding, consists of a polymeric cage with raceway segments made of hardened steel that guide the ball sets inside the complete system. Recirculating balls provide unlimited stroke at low-friction movement, and are used for carrying heavier loads.

Linear motion bearings generally use a pad, bushing, or roller system to carry a load on a rail. The rail can vary in length, and isn’t necessarily set in a straight line. Rails can come in many profiles – flat surfaces, round polished rods, or polished ground surfaces. Hard and ground bearing surfaces work best. Miniature linear bearings work well in a micro-scale applications, whereas larger industrial models are capable of carrying tons.

Bushings provide the simplest linear bearings, and are often referred to as slides. These are thin-walled cylinders that can be injection molded from a range of polymers, and infused with a lubricant. An oil-infused bronze design rides on a polished round rod.

Sometimes only purpose-built linear bearings are required for tasks, not those built for permanent use, such as pull-out equipment drawers or store-able work surfaces. Accessories called wipers are employed to sweep dirt and debris from in front of the bearing as it rolls along the rail. Durability of the bearing is determined by the load and required speed.

All the major bearing manufacturers have designed linear motion bearings for your most difficult application needs. Take a look at their websites, and talk to your distributor for more details.

Timken’s New UC-Series Ball Bearing Housed Unit Line

Friday, May 1st, 2015

Timken is a leading manufacturer of bearings and other machine parts on the market today.

Known for its quality products, Timken ended with $3.1 billion in sales in 2014 (Source: BearingNews.com), this is because they take care to regularly apply their vast knowledge of metallurgy across today’s broad spectrum of bearings, as well as related systems, in order to improve equipment reliability and efficiency.

In this post, we’ll put the spotlight on Timken, and the new housed product line they rolled out earlier this year:

The UC Series Ball Bearing Housed Unit Line

Timken came out with this new housed unit line in response to market demand for standard-duty metric and imperial ball bearing housed units. Together with the new UC series, Timken now offers its international customers a wide range of ready-to-go units, complete with five housed designs.

Housed units are useful in that they provide enhanced bearing protection in a multitude of harsh conditions. Timken’s housed units feature powerful sealing options, helping to enhance bearing protection in debris-filled, contaminated, or high-moisture environments.

The pressures to reduce build times and costs have led to greater integration of component parts in all areas of manufacturing. By providing units that are pre-assembled, ready to bolt into place, designers can easily and economically solve specific bearing problems.

The UC series ball bearing housed units are offered in an extensive range of sizes – for shafts from 12 mm to 90 mm. The most common industry-used sizes are in stock to best accommodate immediate delivery needs. Housed units are beneficial specifically for bearings with spherical outer rings, where outer ring rotation is minimized with the help of precision-machined cast-iron housings.

The new product line features wide inner ring ball bearings, a set screw locking design, bonded seals with a steel flinger, and precision-made cast-iron housings. They are designed for normal operating conditions, between −20° C and 100° C.

Manufactured to rigorous testing and high quality standards, these highly versatile units are high-strength and suited for most industrial applications.

Industries and Applications for these new housed units (Source Timken.com):

  • Materials Handling
  • Food and Beverage Machines
  • Agriculture
  • Packaging
  • Industrial Fans/Blowers
  • Glass Making
  • Brick Making
  • Paper and Printing